During a Reiki treatment the client lays down fully clothed in a quiet safe space, meditative gentle music is very useful in creating a nice environment. You should make sure that you are not going to be disturbed for the length of the session. So make sure that the phone is switched of and you will not be having any interruptions. Make sure that your client is warm and comfortable, a mattress on the floor makes a good treatment area but make sure that you can get all around your client and wont make yourself stiff by bending to much.
You can then state your intention to give a healing session, for example: I intend to give (name) a Reiki healing, I ask that all energies flow for the highest good in accordance with divine will. You can then sit quietly for a moment, draw your Reiki symbol, place your hands in the prayer position and imagine the healing energy entering your crown chakra and flowing down to your palms.
You can then begin by placing your hands in the positions listed and holding them there for 3-5 minutes. If you are sensitive you may feel a warmth or tingling sensation your hands. When the sensations subside a little you can then move to the next position. Try to be as quiet as you can and see if you can get a sense of where to place your hands, the person may have a weak area that needs more energy. Try to let your intuition guide you, and to feel what is happening with the sensations.
To finish a Reiki treatment session you may like to sweep you hands slowly down the clients aura, starting at the crown and moving slowly down the body towards the feet. Do this three times. Make sure that your client is fully grounded before they get up and move about. The more practice that you get the easier it will be, so try to share Reiki treatments as often as you can.
It is very helpful to keep records of all your healing sessions. You might want to keep a spiritual journal detailing your Reiki journey. In it you can record all your feelings and experiences as your Reiki path unfolds.